Mikhail Beketov, the editor-in-chief of Khimkinskaya Pravda, was found guilty of slandering Vladimir Strelchenko, the mayor of Khimki, a town on the edge of Moscow.

Civil rights campaigners condemned the ruling, which came days after another journalist, Oleg Kashin, was nearly beaten to death in the Russian capital. "This judgment shows that the courts have bowed in front of the local administration," said Alexei Simonov of the Glasnost Defence Foundation. "It is absurd."

Beketov, 52, was attacked in November 2008 after his newspaper supported a campaign to save a forest in Khimki that is destined to be cut down to make a new government-funded road. He has since undergone eight operations, including amputation of three fingers and the lower half of one leg, and a procedure to extract shards of skull from his brain tissue. He cannot speak and uses a wheelchair.

The court fined Beketov 5,000 roubles (£100) but ordered that the sum need not be paid, on a technicality. The prosecution related to an incident in 2007 in which Beketov, whose car had been burned in an arson attack, gave a television interview accusing Strelchenko of "political terror". His lawyers said they would appeal.

The ruling caused fresh outrage among journalists and rights activists already angry over the attack on Kashin, 30, early on Saturday morning.

Two men pounced on the reporter for the daily newspaper Kommersant as he returned home to his apartment in central Moscow. The men beat him methodically with an iron bar for 90 seconds, leaving him with a fractured skull, broken fingers, a broken leg and a smashed jaw.

One of the main suspected motives is revenge for Kashin's writing about Kremlin-backed youth groups, or about the Khimki forest debate.

Journalists came and wenttoday from a picket outside Moscow police headquarters at Petrovka 38. They took turns to hold a sign saying: "The journalist Oleg Kashin was beaten. I demand that those who ordered and carried out the crime are found." Russia's president, Dmitry Medvedev, promised on Monday that the attempted murderers would be found.

Kashin's wife, Yevgeniya Milova, told a press conference his condition had slightly improved but he remained heavily sedated as doctors monitored his progress.

"I think everything will be fine, but he won't be completely well for a long time," she said.

Also today, Anatoly Adamchuk, a journalist also allegedly beaten in Zhukovsky, near Moscow, at the weekend, said police officers came to his hospital bed last night and pressured him to admit he had staged the attack. "Maybe they think I smashed my own face against a tree or something," he said.

Police later released a statement saying Adamchuk, 36, had paid a kickboxing enthusiast and his friend 1,000 roubles to strike him "lightly". But his editor at Zhukovskiye Vesti, Natalya Znamenskaya, said the attack was probably revenge for the paper's critical reporting on a road project similar to the one in Khimki